From ba9255f6b00dbc2670727655259cb1781159809f Mon Sep 17 00:00:00 2001
From: Zeke Gabrielse <ezekg@yahoo.com>
Date: Fri, 8 Nov 2024 10:49:26 -0600
Subject: [PATCH] refactor npm worker to use enumeratorio

---
 app/workers/process_npm_package_worker.rb     | 33 ++++++++++++++-----
 .../process_npm_package_worker_spec.rb        | 15 +++++----
 2 files changed, 32 insertions(+), 16 deletions(-)

diff --git a/app/workers/process_npm_package_worker.rb b/app/workers/process_npm_package_worker.rb
index ff1adfccef..61ba022e9b 100644
--- a/app/workers/process_npm_package_worker.rb
+++ b/app/workers/process_npm_package_worker.rb
@@ -20,14 +20,24 @@ def perform(artifact_id)
       raise PackageNotAcceptableError, 'unacceptable filesize'
     end
 
-    # download the package tarball
+    # download the package tarball in chunks to reduce memory footprint
     client = artifact.client
-    tgz    = client.get_object(bucket: artifact.bucket, key: artifact.key)
-                   .body
+    enum   = Enumerator.new do |yielder|
+      client.get_object(bucket: artifact.bucket, key: artifact.key) do |chunk|
+        yielder << chunk
+      end
+    end
 
-    # unpack the package tarball
+    # wrap the enumerator to provide an IO-like interface
+    tgz = EnumeratorIO.new(enum)
+
+    # gunzip the package tarball
     tar = gunzip(tgz)
 
+    # keep a ref to the manifest
+    manifest = nil
+
+    # unpack the package tarball
     unpack tar do |archive|
       # NOTE(ezekg) npm prefixes everything in the archive with package/
       entry = archive.find { _1.name in 'package/package.json' }
@@ -42,21 +52,25 @@ def perform(artifact_id)
         entry.size > MAX_MANIFEST_SIZE
 
       # parse/validate and minify the manifest
-      json = JSON.parse(entry.read)
-                 .to_json
+      content = JSON.parse(entry.read)
+                    .to_json
 
-      ReleaseManifest.create!(
+      manifest = ReleaseManifest.create!(
         account_id: artifact.account_id,
         environment_id: artifact.environment_id,
         release_id: artifact.release_id,
         release_artifact_id: artifact.id,
-        content: json,
+        content:,
       )
     end
 
-    # not sure why GzipReader#open doesn't take an io?
+    # not sure why GzipReader#open doesn't take an IO ala every other IO-like?
     tar.close
 
+    # we can assume package tarball is invalid if there's no manifest
+    raise PackageNotAcceptableError, 'manifest is missing' if
+      manifest.nil?
+
     artifact.update!(status: 'UPLOADED')
 
     BroadcastEventService.call(
@@ -68,6 +82,7 @@ def perform(artifact_id)
          ActiveRecord::RecordInvalid,
          JSON::ParserError,
          Zlib::Error,
+         Minitar::UnexpectedEOF,
          Minitar::Error,
          IOError => e
     Keygen.logger.warn { "[workers.process-npm-package-worker] Error: #{e.class.name} - #{e.message}" }
diff --git a/spec/workers/process_npm_package_worker_spec.rb b/spec/workers/process_npm_package_worker_spec.rb
index 2bc87968e0..79fbab5b57 100644
--- a/spec/workers/process_npm_package_worker_spec.rb
+++ b/spec/workers/process_npm_package_worker_spec.rb
@@ -15,15 +15,16 @@
   after  { Sidekiq::Testing.fake! }
 
   context 'when artifact is a valid package' do
-    let(:package)      { file_fixture('hello-2.0.0.tgz').open }
-    let(:package_json) {
-      tar  = Zlib::GzipReader.new(package)
-      json = Minitar::Reader.open tar do |archive|
+    let(:package_fixture) { 'hello-2.0.0.tgz' }
+    let(:package_tarball) { file_fixture(package_fixture).open }
+    let(:package_json)    {
+      tgz = file_fixture(package_fixture).open
+      tar = Zlib::GzipReader.new(tgz)
+
+      Minitar::Reader.open tar do |archive|
         archive.find { _1.file? && _1.name in 'package/package.json' }
                .read
       end
-
-      json
     }
 
     let(:minified_package_json) {
@@ -32,7 +33,7 @@
     }
 
     before do
-      Aws.config = { s3: { stub_responses: { get_object: [{ body: package }] } } }
+      Aws.config = { s3: { stub_responses: { get_object: [{ body: package_tarball }] } } }
     end
 
     context 'when artifact is waiting' do